Sealed photographic film roll



March 3, 1953 o. E. woLFF SEALED PHOTOGRAPHIC FILM ROLL 2 SHEETS-SHEET 2 Filed Oct. 50, 1948 VENTOR M .25%

atentec Mar. 3, 195,3

SEALED PHOTOGRAPHIO FILM ROLL Otto E. Wolff, Cambridge, Mass., assignor to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware Application October 30, 1948, Serial N o. 57,564

Claims.

This invention relates to photography and more particularly to a novel photographic sheet material which is in roll form for insertion in a camera, the roll of sheet material being arranged so as to be unrolled within the camera during use. This invention is especially directed to improved photographic products for use in cameras of the type described in the copending iapplication of Joseph F. Carbone et al., Serial No. 7 80,344, filed October 17, 1947, for Self-Developing Camera (now Patent No. 2,455,111, issued November 30, 1948).

A principal object of the present invention is to provide a novel arrangement of such a roll of photographic sheet material wherein a rupturable seat is provided for maintaining the sheet in rolled-up form during handling while permitting easy breaking of this seal after the rolled-up sheet has been positioned in the camera and a leader, forming a part of the sheet, is pulled to advance the sheet within the camera.

Another object of the invention is to provide two such rolls of sheet material, one roll being a photosensitive sheet and the other roll being an image-carrying sheet, each roll containing a rupturable seal and an extending leader, the two leaders being joined together to provide a composite product which may be readily inserted in the camera with no danger of the sheets becoming prematurely unrolled.

Still another object of the invention is to provide a one or two roll product which is simple and cheap to manufacture and assemble.

These and other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the product possessing the features, properties and the relation of components which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings where- 1n:

Figure 1 is a diagrammatic isometric view, with portions cut away, of one preferred form of the invention, a preferred type of camera for using the product being shown in dotted lines in operative relationship to the product;

Fig. 2 is a diagrammatic plan view of the outer surface of the photosensitive sheet in unrolled form showing a preferred type of rupturable seal therefor; 1

Fig. 3 is a diagrammatic plan view of the outer surface of the image-carrying sheet in unrolled form showing a preferred type of rupturable seal therefore; and

Fig. 4 is an enlarged schematic diagrammatic sectional view of the rupturable seal of Fig. 2 when the product of Fig. 2 is in its rolled form.

In general this invention relates to a photographic product comprising a sheet of photographic material formed into a roll. The outer layers of the rolled photographic sheet constitute a leader for threading the sheet through a photographic apparatus such as a camera, two of the outer layers of the leader being sealed together by a rupturable seal. This invention is particularly directed to an improved type of such seal for maintaining the sheet in rolled-up condition, this seal being suiciently strong to maintain the sheet rolled up during normal handling of the product but being readily ruptured when that portion of the leader extending beyond this seal is pulled after the rolled-up product has been positioned in the camera. This seal preferably comprises a limited area of a pressure-sensitive adhesive associated with a portion of the leader and so positioned as to contact, and adhesively unite, this leader portion to the next inner layer of the leader in the roll. That portion of the next inner layer of the leader, to be contacted by the pressure-sensitive adhesive, preferably has a smooth surface stratum to which the adhesive will adhere sufficiently strongly to prevent accidental rupturing of the seal but from which the adhesive is cleanly stripped when the leader is pulled to unroll the sheet. The portion of the leader, which is associated with the seal, preferably includes at least one hole therein and the seal preferably comprises a strip of tape secured to the outer surface of the leader and at least partially covering this hole. This tape has a pressure-sensitive adhesive coating on that surface thereof adjacent the leader. The next inner layer of the leader preferably includes a smooth-surfaced strip of tape secured to that portion of the surface of the leader which underlies the hole when the leader is in its rolled-up condition. The outer smooth surface of this strip of tape thereby provides the surface stratum from which the pressure-sensi- Y tive adhesive tape is cleanly stripped. In a preferred product of the present invention, there is provided a roll of a photosensitive sheet, such as a silver halide, and a second roll of an imagecarrying sheet, these two sheets being arranged to be brought into face-to-face contact after exposure of the photosensitive sheet so as to produce a negative image on the photosensitive sheet and a positive image on the image-carrying sheet by releasing a processing liquid from a container preferably secured to the inner surface of the image-carrying sheet. In a preferred form of the invention both the image-carrying sheet roll and the photosensive sheet roll include rupturable seals of the type mentioned above.

Referring now to the drawings, where like numbers refer to like elements in the various gures, the composite product is shown as a two-roll assembly comprising one roll it of the photosensitive sheet and another roll i?. of the image-carrying sheet. The photosensitive sheet I0 is preferably Wound on a spool i4 and comprises a photosensitive portion i6 having a silver halide photosensitive layer It on the inner surface thereof. A portion of the photosensitive sheet te comprises a leader 2i) which is preferably secured to the photosensitive portion i thereof along a transversely tapered connection 22 by means of a pressure-sensitive adhesive tape 24. The rupturable seal, generally indicated at 26 in Fig. l, preferably comprises a strip 28` of a pressure-sensitive. adhesive tape, this strip 2S overlying a pair of holes 30 in the photosensitive sheetv leader 2B. In a preferred form of the invention strip 28 is preferably longer than the circumference of the roll so that one end of the strip underlies that portion of the strip 2S which is positioned over the holes 3d.

In assembling the roll of photosensitive sheet lil, leader 2Q is preferably pierced by a suitable die to form the two holes 3B and then the strip 2S is placed over the two holes 3Q with its pressuresensitive adhesive coating 32 adjacent the leader 2U, VThe strip 28 is firmly pressed against the outer surface of the leader 2B so that the pressure-sensitive coating 32 firmly bonds the strip 28 to the leader 2d. A predetermined length of photosensitive silver halide sheet is out from a supply thereof andl secured to the leader 2li by means of the adhesive tape 24. The end of the photosensitive sheet is then secured to the spindle :i

of spool I4, such as bypassing a tapered end of the sheet through a slot of the spool, and the photosensitive sheet and the leader are then Wound up on the spool. During this. Winding operation, pressure is applied to at least the outer layers of the leader 29 to press the pressuresensitive coating 32 through the holes Sil so that coating 32 thereby contacts and adheres to the outer layer of strip 28 on the next inner layer of thev leader. The formation of the rupturable sealA by this pressing operation is shown in greater detailin Fie,-` l Where the variousV elements are shown. in enlarged form.

As, canbe Seen best in Fig. 4, the pressuresensitive` adhesive coating 32, carried by the outer layer of strip 28is pressed into adhesive contact with the outer surface of the inner layer of strip 28, Since the outer surface of this inner layer of strip 2B isrelatively smooth and nonbrous,

the adhesive coating 32 does not adhere thereto so strongly as to prevent separation thereof duringV unrolling ofY the leader from the roll of photosensitive sheet. However, the pressuresensitive adhesive coating 32 does adhere to this innermlayerl surface sufficiently tightly to permit the roll of photosensitive sheet to be handled Without much care during loadingV of the camera, For example, the spool can be supported solely by thatvportion of the leader extending from the seal Without causing the seal to rupture.

The preferred form of image-carrying sheet i2 is shown in Fig. 3 as comprising a portion dii including a plurality of image areas c2 sequentially arranged on the inner surface thereof. Each of these image areas 42 is preferably defined by perforations 43 extending around the boundary of each image area. Associated with each image area there is preferablyA provided a container 44 positioned on the inner surface of the image-carrying sheet and releasably carrying a i processing liquid. A hole i5 is preferably iri-` cluded in the image-carrying sheet adjacent a transverse edge of each image area to assist in tearing out each processed image area along the lines defined by the perforations d3. The imagecarrying sheet has a portion forming a leader 46, this portion being preferably integral with portion lid, and the leader 126 being preferably some- What shorter than the leader 2i) for the photosensitive sheet lil. Near the outer end of the image-carrying sheet leader it there are provided two holes 48, these holes being covered by strip ED of a pressure-sensitive adhesive tape similar to strip 2S associated with the photosensitive sheet leader 23, A second strip 52 of a pressure-sensitive adhesive tape is applied to the same surface of the leader :iii so as to be in posi'- tion to underlie the holes '1i-8 when the imagecarrying sheet is rolled up. Suitable indiciaA 55 are preferably included on the, back surface of image-carrying sheet i2 to aid in properly positioning the two sheets during use. when forming a roll of the image-carrying sheet l2, the inner end thereof is held by a suitable ceiling mechanism and the sheet is rolled upon itself, no spool being employed in this case. As the end of the image-carrying sheet leader is wound around the roll, the outer layers ofy the-leader are pressed against the formed' roll so as to cause'the pressure-sensitive adhesive coating, carried by outer strip 55, to be forced through holes if?, and to contact` and adhere to the outer surfaceof inner strip d2 tocreate the rupturable seal which is indicated at d? in Fig. l. There is thus formed thev same kind of rupturableseal as mentioned in the description of the photosensitive roll iii and shown in detail in Fig; 4.

The free end of the leader 4S, on the'imagee carrying sheet,- is then preferably join-ed to the leader 2d, extending; fromv the photosensitive roll i0. The junction between these'two leaders is preferably formed by the use ofa stripof thermoplastic adhesive coated tape 5ft, thus forming-aV relativelyl permanent bond between these two leaders. That portion ofthe photosensitive'sheetVA leader 2d extending beyond-'thejunction of the two leaders is preferablywrapped around* the two rolls duringthemanufactureof the product so as to-form aA compact assemblagewhich may be read-ilyV handled and packaged. In order to prevent unrolling of the outer end of the photosensitive sheet leader 2li, itis preferably-temporarily sealed by means such-asa' strip 53k of pres'- sure-sensitive adhesive.

In a preferredv form of the invention, the photosensitive portionV l of sheet i'efcomprises a suitable paper base carrying a relatively fast silverAv halide photosensitivelayer i8,- such asi a layer of a gelatine` silverl iodobromide emulsion.

rlhe leader 2d preferably comprises the usual' leader stock such as' duplexredv and blaclapaper, Knowlton grade 605, the leader being very slightly vwider `than thephotosensitive portion i t seas to-form a-gocd lightV seal. The spool iii is preferably a molded styrene-which includes a ller for rendering the styrene opaque -to -actinic light. The image-carrying sheet I2 preferably comprises baryta paper-Which has been' treated in accordance with the teachings in the'copending' application of Edwin H. Land, Serial No. 790,603, filed December 9, 1947, for Photographic Apparatus (now Patent No. 2,520,641, issued August 29, 1950)', and the liquid in container fill preferably comprises a viscous aqueous alkalineY solution of a developer and a silver halide solvent 5 in the proportions listed in said copending application of Edwin H. Land.

The various strips of pressure-sensitive adhesive 28, 50 and 52 preferably comprise smooth lustrous noniibrous sheeting such as transparent cellulosic iilms, i. e., regenerated cellulose and cellulose lacetate or other synthetic and natural materials such as resins. The sheeting has a pressure-sensitive adhesive coating rmly united thereto. Equally, the sheeting may comprise a fibrous support having the adhesive on one surface and a smooth coating on the other surface. Examples of such tapes are those sold by the Minnesota Mining and Manufacturing Co. under the trade-mark Scotch Tape. One particularly useful tape of the above type is that sold under the trade-mark Acetate Fibre. Numerous examples of the methods of preparing such tapes are given in United States Patents 2,156,380 and 2,183,330. The pressure-sensitive adhesive tape 24, sealing leader 2li to the photosensitive portion I6 of the photosensitive sheet, preferably comprises a black cellulose acetate tape of the same type as mentioned above. A similar adhesive tape is used for adhesive strip 58.

The camera til, for which the product described 4above is particularly adapted, is shown in dotted lines in Fig. 1 as comprising a front housing $2 and a rear housing 64. A suitable lens and shutter assembly 65 is connected to front housing t2 by means of the usual bellows 68. For processing the composite product, by releasing the processing 4liquid from container 44 and spreading the released liquid between superposed areas of the two sheets, there is provided a pair of pressure rolls 1li. Front pressure roll 10 is preferably carried by a partition, not shown, while the rear pressure roll l is preferably carried by the rear housing t4. The details of such a camera aredescribed and claimed in the above-mentioned i copending application of Carbone et al.

In the use of the preferred modification of the invention described above, the strip 5B, which holds the end of the photosensitive leader 2li around the two rolls, is removed thereby permitting the outer end of leader 20 to be unwound so that the tworolls are free to be separated as shown in Fig. l. The rear housing 64 of the camera is swung open, as is the partition which carries the front roll l. Spool I4 is then positioned in a suitable spool holder, preferably carried by the partition, and the photosensitive sheet leader 2li is led along the front of the partition and around roll l0. The roll of image-carrying sheet i2 is then placed in the position shown, its leader 4E and the outer end of the photosensitive sheet leader 20 being led along the rear of the partition till the end of leader 2U extends from the right-hand end of the camera. The rear housing 54 is then closed, thus making the camera body light-tight. At this point the two seals 26 and 41, associated with the two rolls, are still intact and they thus prevent unrolling of these two sheets till the camera has been made completely light-tight. That portion of leader 20 which eX- tends from the camera is now pulled, thus also pulling the leader 4B so as to break both seal 26 on the photosensitive roll and seal 41 on the image-carrying sheet roll. Further pulling of the leader 2o unwinds the leaders from both rolls and moves an unexposed area of the photosensitive sheet into exposure position in the camera. At the same time, the first image area 42 is moved into position where its associated container is about to pass between the pressure rolls 10. This proper positioning is indicated by aligning the'V first indicium 56 on. the back of the image-carrying sheet with a portion, such as the right-hand end, of the camera. During this movement of the photosensitive sheet I0 the tapered connection 22 permits the relatively thick portion of sheet IU to pass between pressure rolls 1U without greatly increasing the pull force. The photosensitive area in exposure position is now exposed and those portions of the two leadersextending from the right-hand end of the camera are again pulled to advance the two sheets between the pressure rolls 10. This advancement allows the pressure rolls to release the processing liquid from the first container 44 and spread this liquid between the exposed photosensitive area and the rst image area 42, laminating these two areas together and accomplishing a predetermined processing thereof. This processing preferably comprises the concurrent development of a negative image in photosensitive layer i8 and the formation of a positive image on the image area 42. After a predetermined time, such as one minute, a back door in rear housing 64 is opened, the camera user inserts a fingernail through the hole t5 and tears out the processed image areaL 42, this removal being assisted by perforations 43.

While preferred materials and processes have been described in connection with the discussion of the invention, it should be understood that the invention is of wide application. Other materials and processes than those speciiled may be employed. For example, other photosensitive materials and processing liquids may be used to record negative or positive images.

Since certain changes may be made in the above product without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A composite photographic product comprising a length of sheet material formed into a roll, the outer layers of said rolled-up sheet constituting a leader for threading said sheet into a photographic apparatus, and a rupturable seal sealing one of said outer layers to the next inner layer so that the layers of said roll beneath said lastnamed outer layer are kept from unwinding, a portion of the length of said sheet material extending beyond said seal and being free to unwind from said roll without rupturng said seal, said portion constituting the free end of said leader, said leader having at least one hole therein at said seal, said seal Comprising a strip of tape secured to the outer surface of saidl leader and at least partially covering said hole, and a pressure-sensitive adhesive coating on that surface of said tape adjacent said leader, said strip being suiiiciently long to cover that portion of the next inner layer of said rolled-up sheet which underlies said hole, said coating having less affinity for the outer surface of the inner layer of said tape than for said leader.

2. The product of Iclaim 1 wherein the sheet material formed into ya roll is a photosensitive silver halide iilm and the inner layers of said roll include a silver halide stratum while the outer layers of said roll comprise a light-opaque material which constitutes the leader.

3. A composite photographic product comprising a length of sheet material formed into a roll,

the outer layers of said rolled-up sheet constituting' a leader for threading Said; sheet into a, photographie. apparatus, and a rupturableseal sealing, one of said outer layers to the .next inner layer so that the layers of, said roll beneath Sai-d last-named outer layer-fare kept from unwindine, a portion of the length ofsaid sheet material ex tending beyond said seal and being ree. to un. wind` from said roll Without rupturing said Seal, said portion constituting the free end of said leader, said leader having at least one hole therein at. said seal, said seal comprising tape in strip form secured to the outer surface of. said leader and including a portion of tape which at least partiallyl covers said hole and also a portion of tape which covers that part of the next inner layer of said rolled sheet. which underlies Said hole, and a pressure-sensitive adhesive coating on that surface of said tape adjacent said leader, said coating having less affinity for the outer SL11?- face of the tape portion which underlies said hole. than for said leader.

4. The product of claim 3 wherein the sheet material formed intoa roll is a photosensitive silver halide lm and the inner layers of said `roll include a silver halide stratum while the outer layers of said roll comprise a light-opaque material which constitutes the leader.

5. The product of claim 3 wherein the sheet material formed into a roll comprises an elongated.. flexible, imagefreeivlns. sheetmeterial lier` The following references are ofy record in the ille` of this patent:

UNITED STATES .PATENTS Number Name Date 709,053 Shaw Sept.. 1 0, .1902 778,403 Cline Dec. 27, 1904 S23-,624n McCurdy June 1 9 1906 1,180,415 Nasief Apr 2 5, 1916 1,255,017 Jan. 29, 19,18 1,372,593 Mar. 212, 1921 1,454,045 May 8, 192.3 1,536,341 May 5. 1925 1,858,585 Gantnier May 1.7', 193.2 1,910,287 Henderson May 23'I 193:3 1,969,858 Schnitzler Aug. 14,` 1934 2,188,779v Roehrl Jan. 30., i940 2,332,474 Schusterman Oct'. 19, 19.43

FOREIGN PATENTS Number Country Date 469,653 Great Britain, July 29, 1937 

1. A COMPOSITE PHOTOGRAPHC PRODUCT COMPRISING A LENGTH OF SHEET MATERIAL FORMED INTO A ROLL, THE OUTER LAYERS OF SAID ROLLED-UP SHEET CONSTITUTING A LEADER FOR THREADING SAID SHEET INTO PHOTOGRAPHIC APPARATUS, AND A RUPTURABLE SEAL SEALING ONE OF SAID OUTER LAYERS TO THE NEXT INNER LAYER SO THAT THE LAYERS OF SAID ROLL BENEATH SAID LASTNAMED OUTER LAYER ARE KEPT FROM UNWINDING, A PORTION OF THE LENGTH OF SAID SHEET MATERIAL EXTENDING BEYOND SAID SEAL AND BEING FREE TO UNWIND FROM SAID ROLL WITHOUT RUPTURING SAID SEAL, SAID PORTION CONSTITUTING THE FREE END OF SAID LEADER, SAID LEADER HAVING AT LEAST ONE HOLE THEREIN AT SAID SEAL, SAID SEAL COMPRISING A STRIP OF TAPE SECURED TO THE OUTER SURFACE OF SAID LEADER AND AT LEAST PARTIALLY COVERING SAID HOLE, AND A PRESSURE-SENSITIVE ADHESIVE COATING ON THAT SURFACE OF SAID TAPE ADJACENT SAID LEADER, SAID STRIP BEING SUFFICIENTLY LONG TO COVER THAT PORTION OF THE NEXT INNER LAYER OF SAID ROLLED-UP SHEET WHICH UNDERLIES SAID HOLE, SAID COATING HAVING LESS AFFINITY FOR THE OUTER SURFACE OF THE INNER LAYER OF SAID TAPE THAN FOR SAID LEADER. 